github.com/m3db/m3@v1.5.0/src/cluster/placement/compress.go (about)

     1  // Copyright (c) 2021 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package placement
    22  
    23  import (
    24  	"github.com/gogo/protobuf/proto"
    25  	"github.com/klauspost/compress/zstd"
    26  
    27  	"github.com/m3db/m3/src/cluster/generated/proto/placementpb"
    28  )
    29  
    30  const _decoderInitialBufferSize = 131072
    31  
    32  func compressPlacementProto(p *placementpb.Placement) ([]byte, error) {
    33  	if p == nil {
    34  		return nil, errNilPlacementSnapshotsProto
    35  	}
    36  
    37  	w, err := zstd.NewWriter(
    38  		nil,
    39  		zstd.WithEncoderCRC(true),
    40  		zstd.WithEncoderConcurrency(1),
    41  		zstd.WithEncoderLevel(zstd.SpeedBestCompression))
    42  	if err != nil {
    43  		return nil, err
    44  	}
    45  	defer w.Close() // nolint:errcheck
    46  
    47  	uncompressed, _ := p.Marshal()
    48  
    49  	compressed := make([]byte, 0, len(uncompressed)/2) // prealloc, assuming at least 50% space savings
    50  	compressed = w.EncodeAll(uncompressed, compressed)
    51  
    52  	return compressed, nil
    53  }
    54  
    55  func decompressPlacementProto(compressed []byte) (*placementpb.Placement, error) {
    56  	if compressed == nil {
    57  		return nil, errNilValue
    58  	}
    59  
    60  	decompressed := make([]byte, 0, _decoderInitialBufferSize)
    61  	r, err := zstd.NewReader(
    62  		nil,
    63  		zstd.WithDecoderConcurrency(1),
    64  		zstd.WithDecoderLowmem(false),
    65  	)
    66  	if err != nil {
    67  		return nil, err
    68  	}
    69  	defer r.Close() // nolint:errcheck
    70  
    71  	decompressed, err = r.DecodeAll(compressed, decompressed)
    72  	if err != nil {
    73  		return nil, err
    74  	}
    75  
    76  	result := &placementpb.Placement{}
    77  	if err := proto.Unmarshal(decompressed, result); err != nil {
    78  		return nil, err
    79  	}
    80  
    81  	return result, nil
    82  }